The operators know it well, that magical button we push that cleans everything as if we alone possess supernatural powers! But in fact, do we? It’s been my experience that we do not. While it’s safe to say the chemicals or heat are doing much of the work, it still is dependable on several factors as to whether a system is getting cleaned properly or not. Take for example a cultured dairy plant that wanted to run a non-cultured product through their system. After cleaning and sanitizing their system completely, the non-cultured product over shelf life started to exhibit the same flavor, smell and texture of some of the cultured products they made. Not only that, we were able to culture out of those products their original culture organisms. Without a doubt, they had biofilms of their product cultures adhering to the surfaces within their system. Oddly enough, this was a surprise to them. Then again, not many cultured plants will attempt to run a non-cultured product in a cultured product plant. Whether you’re a cultured plant or a fresh product dairy processor, it’s possible to have low level biofilms in your systems, it just tends to be more obvious in fresh product plants (no competition).
Often, plants don’t pay any attention to their CIP systems, however there are a few things that come into play that you need to think about. The power/speed of the circulation pump is critical to give you the volume of flow required to adequately clean and sanitize an enclosed CIP loop. Restrictions and expansions in piping can change the velocity of cleaning solutions. When cleaning volume of flow and turbulence are important. If you are unsure you are getting proper flow, your chemical supplier should have an instrument that they can hook up to the outside of your lines to check the actual flow during CIP. If you have restrictions/expansions, I recommend testing the flow in several different locations within the CIP loop. And always remember the acronym TACT, which are the four tenets of cleaning: Temperature of the solution, Action of flow through the CIP circuit (speed/turbulence), Concentration of chemical, and Time of contact.
